Ed Glaeser is a productive man. Here is his new Editorial in the LA Times. I am familiar with the subject. If you'd like to read our academic paper on this subject then go to Glaeser/Kahn paper .
One valid criticism of this work is that we need to factor in the carbon content of shipping water to thirsty California cities. Currently the pricing (at a penny a gallon or less) is so crazy that this encourages waste. This energy/water footprint would be much smaller under "sensible" pricing.